What is the Quantum Internet?
Scientists believe it will be particularly useful for problems involving multiple variables, such as analyzing financial risks, encoding data and studying the properties of materials.
Researchers suspect that individuals will own personal quantum computers in the near future. Instead, they will be hosted in academic institutions and private companies, where they will be accessible via a cloud service.
How does the quantum internet work?
Quantum computers use fundamental units of information similar to bits used in classical computing. These are called “qubits”.
However, unlike conventional computer bits, which convey information as 0s or 1s, qubits convey information through a combination of quantum states, which are unique conditions found only at the subatomic scale.
For example, one quantum state that can be used to encode information is a property called spin, which is the intrinsic angular momentum of an electron. Spin can be thought of as a small compass needle pointing up or down. Researchers can manipulate that needle to encode information into the electrons themselves, just as they would with ordinary bits, but in this case the information is encoded in a combination of possible states. In a quantum phenomenon called superposition, qubits are neither 0 nor 1, but both and neither.
This allows quantum computers to process information in a completely different way than their conventional counterparts, and so they can solve certain types of problems that would take even the largest supercomputers decades. These are problems such as factoring large numbers or solving complex logistic calculations (see traveling salesman problem) Quantum computers will be particularly useful for cryptography, as well as for discovering new types of pharmaceuticals or new materials for solar cells, batteries, or other technologies.
But to unlock that potential, a quantum computer would need to be able to process large numbers of qubits, more than any single machine can currently handle. That is, until multiple quantum computers can be connected via a quantum internet and their computing power combined to create a much more capable system.
There are several different types of qubits under development, and each has distinct advantages and disadvantages. The most common qubits studied today are quantum dots, ion traps, superconducting circuits, and vicious spin qubits.
What can the quantum internet do?
Like many scientific advances, we won’t understand everything the quantum internet can do until it’s fully developed.
60 years ago, few could have imagined that a few interconnected computers would one day create the sprawling digital landscape we know today. The quantum internet presents a similar unknown, but a number of applications have been theorized and some have already been demonstrated.
Due to the unique quantum properties of qubits, scientists believe that the quantum internet will greatly improve information security, making it nearly impossible to intercept and decipher quantum-encoded messages. Quantum key distribution, or QKD, is a process by which two parties share a cryptographic key over a quantum network that cannot be intercepted. Several private companies already offer the process, and it’s even used ensure national elections.
At the same time, quantum computers pose a threat to traditional encrypted communication. RSA, the current standard for protecting sensitive digital information, is nearly impossible for modern computers to crack; However, quantum computers with enough processing power can crack RSA encryption in minutes or seconds.
A fully realized quantum network could significantly improve the accuracy of scientific instruments used to study certain phenomena. The implications of such a network would be far-reaching, but early interest focused on gravitational waves, microscopic and electromagnetic imaging of black holes.
The creation of a purely quantum Internet would also alleviate the need for quantum information to transition between classical and quantum systems, a significant bottleneck in current systems. Instead, it would allow a set of individual quantum computers to process information as a single conglomerate machine, giving them far more computing power than any single system could handle on its own.
“The quantum internet represents a paradigm shift in how we think about secure global communication,” said David Avshalom, Liew Family Professor of Molecular Engineering and Physics at the University of Chicago, director of the Chicago Quantum Exchange and director of Q-NEXT. , Energy Quantum Information Science Center at Argonne. “The ability to create an entangled network of quantum computers will allow us to send encrypted messages that are unbreakable, keep technology perfectly synchronized over long distances using quantum clocks, and solve complex problems that a single quantum computer can tackle alone; some apps we know about right now. In the future, there are likely to be surprising and impactful discoveries using quantum networks.”
How far is the quantum internet?
To date, no one has been able to successfully create a stable quantum network on a large scale, but there have been major advances.
In 2017, researchers at the University of Science and Technology of China used lasers to transfer successfully entangled photons between an orbiting satellite and ground stations more than 700 miles below. The experiment demonstrated the possibility of using satellites to form part of a quantum network, but the system was able to recover only one photon in every 6 million, too few for reliable communication.
